1. Field of the Invention
The present invention relates to a photosensitive composition capable of changing its properties by undergoing a reaction upon irradiation with an actinic ray or a radiation, a compound for use in the photosensitive composition, and a pattern forming method using the photosensitive composition. More specifically, the present invention relates to a photosensitive composition for use in the production process of a semiconductor such as IC, in the production of a circuit substrate of liquid crystal, thermal head and the like, in other photofabrication processes or in the lithographic printing plate or acid-curable composition, and also relates to a compound for use in the photosensitive composition and a pattern forming method using the photosensitive composition.
2. Description of the Related Art
The chemical amplification resist composition is a pattern forming material capable of forming a pattern on a substrate by producing an acid in the exposed area upon irradiation with a radiation such as far ultraviolet light and through a reaction using this acid as the catalyst, causing change in the solubility in a developer between the active radiation-irradiated area and the non-irradiated area.
In the case of using a KrF excimer laser as the exposure light source, a resin having small absorption in the region of 248 nm and having a basic skeleton of poly(hydroxystyrene) is primarily used as the main component and this is an excellent system capable of forming a good pattern with high sensitivity and high resolution as compared with conventional naphthoquinone-diazide/novolak resin systems.
In the case of using a light source of emitting light at wavelengths shorter than that, for example, in using an ArF excimer laser (193 nm) as the light source, a satisfactory pattern cannot be formed even by the above-described chemical amplification system because the compound having an aromatic group substantially has large absorption in the region of 193 nm.
In order to solve this problem, a resist containing a resin having an alicyclic hydrocarbon structure has been developed for use with an ArF excimer laser.
As for the acid generator which is a main constituent component of the chemical amplification resist, various compounds have been also found and JP-A-2002-23353 (the term “JP-A” as used herein means an “unexamined published Japanese patent application”), JP-A-2003-149812 and JP-A-2003-114523 describe a compound capable of generating an aromatic sulfonic acid upon irradiation with an actinic ray or a radiation.
However, these are not satisfied in many points and various improvements are demanded. For example, in the case of using a wafer having a large aperture, fluctuation of the temperature in the wafer plane at the heating (PEB) by a hot plate or the like after exposure is found to affect the pattern obtained, and the improvement of such PEB temperature dependency is demanded as well as good profile.